This invention is related to the transmission of electrical power between electronic devices without the use of wires. More specifically, the present invention pertains to the transmission of electrical power between electronic devices using ultrasound.
Conventional power transfer into electronic devices requires these devices to be plugged into an electrical outlet. While wireless data transmission is commonplace, wireless power transmission is not, except at extremely low power levels. This is because conventional wireless transmission of electrical power is via electromagnetic waves, which spread the available energy so that only a tiny fraction is available at the receiving end. A significant number of wireless battery chargers use magnetic induction rather than sound energyxe2x80x94e.g. Phillips cordless toothbrush works that way, for example.
In order for any meaningful power to be available at the receiver, the power level at the transmitter becomes impractically high. Any attempt to focus the energy so that the amount of power at the transmitter becomes manageable, requires physically large antennas because the focusing antennas have to be many times larger than the wavelength of the transmitted radiation. There are also issues relating to safety, and electromagnetic interference to other electronic devices.
The use of piezoelectric transducers to convert one form of sound energy or another into electricity is known. In some cases, the sound energy is ambient sound around the device.
U.S. Pat. No. 6,342,776 by Taylor et al. entitled ACOUSTIC CHARGER FOR ELECTRONIC DEVICES Teaches means for charging the battery of an electronic device by converting acoustic energy to electrical current.
U.S. Pat. No. 5,889,383 by Teich, entitled SYSTEM AND METHOD FOR CHARGING BATTERIES WITH AMBIENT ACOUSTIC ENERGY, teaches a system and method for charging rechargeable batteries using power from ambient acoustic waves.
The use of ultrasonic for transmission of power to charge a battery in the pacemaker or RFID tag is known.
U.S. Pat. No. 4,082,097, by Mann, et al. entitled, MULTIMODE RECHARGING SYSTEM FOR LIVING TISSUE STIMULATORS, teaches a system being disclosed for controlling the charging of a rechargeable battery in an implanted human tissue stimulator by means of an external power source. Included in the stimulator are battery protection devices designed to sense the state of charge of the battery and limit the charging current amplitude so as not to exceed a selected maximum based on different criteria including battery state of charge signals from the implanted stimulator which are indicative of the current amplitude and battery state of charge from one of the protection devices are transmitted to an external unit Based on these signals the external unit is operated in one of a plurality of modes to cause the battery to be charged by a current with an optimum safe amplitude irrespective of determined failure of one or more of the battery protection devices. Mann patent assumed that the charging energy is supplied by magnetic induction. It also mentioned means other than magnetic induction. Such as energy may be transferred by light waves, visible or infrared, using solar cells or other light to current flow energy transducers as the pickup device. Also, energy transfer may be by means of sound or vibration waves (subaudible, audible or ultrasonic) by using a piezoelectric crystal or other vibration to current energy flow transducers.
U.S. Pat. No. 5,300,875, by Tuttle, et al. entitled, PASSIVE (NON-CONTACT) RECHARGING OF SECONDARY BATTERY CELL(S) POWERING RFID TRANSPONDER TAGS, teaches a concept of passively recharging the battery of battery backed electronic circuits and in particular utilizing these methods to recharge an RFID transponder""s secondary cell(s). The invention particularly relates to battery backed transponders which contain rechargeable batteries wherein the recharging circuitry of the present invention allows for passive (non-contact) recharging of a battery residing in a transponder unit that may or may not be directly accessible for handling. The passive recharging strategies disclosed include utilizing energy sources such as: 1) a radio frequency (rf) signal generated outside the package; 2) a seismic geophone; 3) seismic piezoelectric accelerometers; 4) photovoltaic cells located outside of the transponder package; 5) infrared p-v cells located inside of the package driven by the heated package; and/or 5) acoustic energy (sonic and ultrasonic) coupled to the recharging circuitry via an acoustic transducer.
Wireless power transmission using microwaves is known. U.S. Pat. No. 5,982,139 and 6,1 AC power source 14,824, by Parise, et al. entitled REMOTE CHARGING SYSTEM FOR A VEHICLE teaches a remote charging system for use with an electrical storage device mounted in an electric or electric/hybrid vehicle. The system includes a power transmission unit capable of transmitting electrical energy to the electrical storage device via a wireless energy beam. The vehicle includes an antenna capable of receiving the wireless energy beam and transferring the electrical energy to the storage device. The vehicle further includes a translocator for transmitting a coded signal to the power transmission unit corresponding to the location of the vehicle and thereby activating the power transmission unit. The power transmission unit receives and locks onto the coded signal and thereby tracks the vehicle during the charging operation. The translocator signal is transmitted until the electrical storage unit reaches a predetermined level of charge.
However, the Parise patent do not give any details as to how the beam is steered, other than a xe2x80x9ctranslocatorxe2x80x9d on the vehicle continuously transmits while the vehicle needs charging.
Therefore, there exists a need for a electric power charging system using directional ultrasound originating from a charger device, in witch the location of a charge receiving device is first located by the charger device, thereby a predetermined charging path is established; and then the charger device is empowered to charge the charge receiving device using directional ultrasound.
A method and apparatus for converting electrical power from a power source such as a battery to electronically focused ultrasound, and converting the electronically focused ultrasound back to electrical power at a compatible receiving device is provided.
A method and apparatus for converting electrical power from a wall outlet to electronically focused ultrasound, and converting the electronically focused ultrasound back to electrical power at a compatible receiving device is provided. The compatible receiving device may be cell phone, PDA, or a notebook computer or other suitable devices.
A method and apparatus for converting electrical power from a power source as a fuel cell to electronically focused ultrasound, and converting the electronically focused ultrasound back to electrical power at a compatible receiving device is provided. The compatible receiving device may be a cell phone, a PDA, or a notebook computer or other suitable devices.
A power unit is provided in which it electronically scans the available space looking for a compatible receiving device (a cell phone, a PDA, or a notebook computer outfitted with the embodiment of this invention). Once the compatible receiving device is located, the power unit focuses its beam on the compatible receiving device, thereby delivering power thereto.
A method and apparatus for converting electrical power from a power source to electronically focused ultrasound, and converting the electronically focused ultrasound back to electrical power at a compatible receiving device is provided. In which an ultrasound transducer array having a set of spaced individual transducers is provided in the XY plane. The ultrasound transducer array generates a pencil thin ultrasound beam in the Z direction when excited by synchronous signals from the ultrasound transducer drivers.
A method and apparatus for converting electrical power from a power source to electronically focused ultrasound, and converting the electronically focused ultrasound back to electrical power at a compatible receiving device is provided. In which after the compatible receiver devices are known within a given region, the beam position electronics of the power unit switches to the power transfer mode of operation. Thereby power is transferred to the compatible receiving device using ultrasound.
Accordingly, a power transmitting device of wireless power transmission system using ultrasound is provided. The power transmitting device includes: a power receiver receiving power from a power source; and an ultrasound power unit using power derived from the power source for generating at least one directional ultrasound beam. The ultrasound power unit includes: a set of ultrasound transducers forming an ultrasound transducer array, wherein the array is a set of spaced individual transducers placed in the X-Y plane disposed to generate an ultrasound beam in the Z direction.
Accordingly a wireless power transmission system using ultrasound is provided. The wireless power transmission system includes a power transmitting device of wireless power transmission system using ultrasound. The power transmitting device has a power processor for receiving power from a power source; and an ultrasound power unit using power derived from the power source for generating at least one directional ultrasound beam. The ultrasound power unit includes: a set of ultrasound transducers forming an ultrasound transducer array, wherein the array is a set of spaced individual transducers placed in the X-Y plane disposed to generate an ultrasound beam in the Z direction; and a power receiving device disposed within having a driver and receiver control electronics for controlling a transmit/receive switch or a voltage regulator.
In power transmitting device of wireless power transmission system using ultrasound, including: a power processor receiving power from a power source; and an ultrasound power unit using power derived from the power source for generating at least one directional ultrasound beam, the ultrasound power unit including: a set of ultrasound transducers forming an ultrasound transducer array, wherein the array is a set of spaced individual transducers placed in the X-Y plane disposed to generate an ultrasound beam in the Z direction. A method is provided in which the steps of: determining a position for at least one receiving device; and sending the ultrasound beam thereto is included.